Even if you've cleaned and regreased everything, sometimes you have to go after the problem with more gusto. A couple things that have happened to me:
#1: I had a creak in the bottom bracket of my Gold Rush with a Shimano cartridge bottom bracket. I took it all apart, greased the threads and mating surfaces, put it together and the creak went away... for a couple weeks. Then it came back. Dissembled, cleaned, greased, reassembled... same situation.
I finally noticed that there was a teeny bit of play between the bottom bracket sleeve and the frame's BB shell when I threaded just the parts in the frame without tightening them up. I think there was enough room there for things to move around even when tightened to the correct torque. I took everything apart, wound a couple layers of Teflon plumber's tape around the threads and put it all back together... and it's been quiet for years.
#2: On my Lightning, I had a persistent creak/click in my bottom bracket area. Thinking that I had a bad bottom bracket, I rebuilt it. Still the same noise. Rebuilt it again, No luck. On the third time, I took everything apart and finally noticed that the pedal threads were dry. I cleaned them, applied new grease, and enjoyed quiet pedaling.
Keep going after it!
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Jeff Wills
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